The present invention relates to an oil pump. More particularly, the invention is an oil pump arrangement for an outboard motor having a water propulsion device powered by an internal combustion engine positioned in a cowling of the motor.
Outboard motors are powered by an engine which is positioned within a cowling of the motor. The engine includes an output shaft which extends downwardly therefrom and is arranged to drive a drive shaft The drive shaft extends to a lower portion of the motor, where it is arranged to drive a water propulsion device of the motor, such as a propeller.
These motors include a lubricating system for providing lubricant to the engine. The lubricating system typically includes an oil pan and an oil pump for drawing oil from the pan and delivering through passages or galleries through the engine.
The oil pump is often driven off of a camshaft of the engine. A disadvantage of this arrangement is that the oil pump is driven at half the speed of the output shaft, and thus at a fairly low speed. In order for the pump to supply the necessary quantity of oil, the oil pump must then be much larger to compensate for its lower drive speed. The enlarge sized of the oil pump conflicts with the desire to keep the engine, and thus the cowling in which the engine is positioned, as small as possible.
An improved oil pump arrangement for an outboard motor of the type having an engine powering a water propulsion device, is desired.
In accordance with the present invention, there is provided an oil pump for a lubricating system of an outboard motor.
The motor is preferably of the type which has a cowling defining an engine compartment and includes a guide member having an upper surface and a lower surface, the guide member positioned in the cowling and generally dividing the engine compartment into an upper part and a lower part. The motor includes a water propulsion device. An engine is positioned in the upper part of the engine compartment within-the-cowling and has an output shaft arranged to drive the water propulsion device.
The lubricating system includes an oil pan positioned below the guide member and an oil passage leading from the pan through the guide member. The oil pump is positioned in the upper part of the engine compartment and is driven by the output shaft of the engine, the oil pump having an oil inlet in communication with the oil passage through the guide member.
In a preferred arrangement, a connecting member is positioned at an end of the output shaft of the engine. The connecting member is connected to the oil pump for driving the oil pump. A drive shaft extends from the connecting part through the oil pump downwardly through the motor for driving the water propulsion device.
Further objects, features, and advantages of the present invention over the prior art will become apparent from the detailed description of the drawings which follows, when considered with the attached figures.